Dietary patterns developed during adolescence may contribute to obesity and eating disorders and may increase risk for several important chronic diseases later in life. Furthermore, the prevalence of overweight has increased significantly, in particular among minority youth and youth from low socio-economic backgrounds. In order to address these growing problems, it is essential to identify which groups of adolescents need to be targeted for intervention and to identify the factors that need to be addressed in interventions. Large gaps exist in our understanding of the factors associated with nutritional intake, physical activity, and weight status > among adolescents.
This study aims to identify the socio-environmental, personal, and behavioral determinants of nutritional intake and weight status among a large and ethnically diverse adolescent population. Study components included:
- focus groups with adolescents,
- school-based surveys and anthropometric measurements with adolescents, and
- parental telephone interviews, and
- a five-year longitudinal follow-up of 2,516 adolescents.
Projects EAT-I and EAT-II (Time 1 and Time 2 data collection) were supported by the Maternal and Child Health Program (Title V, Social Security Act), Health Resources and Services Administration, Department of Health and Human Services (grants MCJ-270834 and R40 MC 00319). Projects EAT-III and EAT-2010 are currently funded by the National Heart, Lung, and Blood Institute, National Institutes of Health (grant R01HL084064).
- Dianne Neumark-Sztainer PhD, MPH, RD, Principal Investigator
- Mary Story, PhD, RD, Investigator
- Marla Eisenberg, ScD, MPH, Investigator
- Jayne Fulkerson, PhD Investigator
- Jerica Berge, PhD, LMFT Investigator
- John Sirard, PhD, Investigator
- Ann Forsyth, PhD, MA, Investigator/Consultant
- Melanie Wall, PhD
- Peter Hannan, Mstat
- Richard LacLehose, PhD
- Nicole Larson, PhD, MPH, RD
- Katie Loth, MPH, RD
Mary Story, PhD, RD is a Professor in the Division of Epidemiology and Community Health and has been a co-investigator on all three phases of Project EAT. Her training is in nutrition and she has worked for several years in the area of child and adolescent nutrition, eating behavior change, and obesity prevention. Her research has focused on factors related to eating behaviors among youth, and school and community-based nutrition interventions. Dr. Story notes “Project EAT is unique because it is one of the largest and most comprehensive nutrition surveys that has been conducted with U.S. adolescents. Most health surveys with adolescents have included just a few questions on nutrition and eating patterns. The scope of Project EAT has allowed us to examine multiple factors that impact eating behaviors of youth, and thus can help us better understand adolescents’ eating habits and develop more effective interventions to improve weight and nutritional health. This project and the multidisciplinary Project EAT team has been fun and rewarding.”
Cheryl Perry, PhD was a co-investigator on Projects EAT-I and EAT-II. She was involved in survey development, data analyses, and scientific writing. Dr. Perry notes that “Project EAT is such a unique and rich opportunity to explore adolescent and young adult eating patterns in depth and see how those are associated with other aspects of their lives.”
Peter Hannan, MStat is a statistician and analyst for Project EAT. His primary interests have been in making sure that analyses are carried out with statistical appropriateness, and in developing ways to avoid dropping of persons from analyses because a person is missing data on a characteristic which is not the main focus of the investigation. He has performed the analyses for a number of the published papers, and in the process, has learned a good deal about the areas of body image, dieting, disordered eating, and how they are affected by characteristics such a racial/ethnic differences, gender, grade level, or socioeconomic status.
Melanie Wall, PhD is an Assistant Professor of Biostatistics at Columbia University. She has been a co-investigator and statistician on Project EAT since 1999. Her research interests are in statistical modeling of behavioral health data, in particular using latent variable models like structural equation models.
Marla Eisenberg, ScD, MPH is an Assistant Professor in the Department of Pediatrics, Division of Adolescent Health and Medicine. She was the Project Director on Project EAT-II and is currently a co-investigator on Project EAT-III, and has been very involved in survey development, data analysis and manuscript writing. As a social epidemiologist, her interests are in the social forces which influence adolescent health behaviors. On Project EAT, she has examined the relationships between weight-teasing and emotional well-being, peer harassment in schools and school success, and family meal patterns and a variety of high risk behaviors.
John Sirard, PhD is an Assistant Professor in the Curry School of Education at the University of Virginia. He has been involved with Project EAT since 2005. Dr. Sirard provides expertise in physical activity assessment and has been involved with survey development for Project EAT-III. His research interests include physical activity measurement in children and adolescents, the effect of the environment on physical activity and sedentary behavior, and the promotion of physical activity for the prevention of overweight and obesity in youth.
Melissa Nelson Laska, PhD, RD is an Assistant Professor in the Division of Epidemiology and Community Health at the University of Minnesota and a co-investigator on Project EAT-III. Dr. Laska’s primary research interests are in environmental and behavioral determinants of excess weight gain during adolescence and young adulthood. Her current work focuses on identifying weight gain prevention strategies for young adults, particularly in targeting influential determinants of nutrition and physical activity within post-secondary campus settings. Dr. Laska received a BS in Nutritional Sciences from Cornell University, and a PhD in Nutrition with a concentration in Epidemiology from the University of North Carolina at Chapel Hill. In addition, she has trained at Vanderbilt University Medical Center and the Children’s Hospital of Philadelphia and is currently a Registered Dietitian.
Ann Forsyth, PhD, MA is a Professor in the College of Architecture, Art, and Planning at Cornell University and a co-investigator/consultant on Project EAT-III. Her training is in city planning and architecture and her work focuses on the social aspects of physical planning, urban design, and urban development. Dr. Forsyth has done work on walkability and the relationship between health and the built environment funded by such organizations as the Robert Wood Johnson Foundation and the National Institutes of Health. She is the editor of two handbooks about using geographic information systems (GIS) to measure the intersections between health and the built environment as well as a collaborator on a number of tools featured on the web site www.designforhealth.net.
Richard Maclehose, PhD is an Assistant Professor in the Division of Biostatistics and in the Division of Epidemiology and Community Health at the University of Minnesota. His interests are in epidemiologic methods, Bayesian analysis and causal inference. Dr. Maclehose has been a statistician on Project EAT since 2009. His contributions to Project EAT involve study design and analysis as well as the development of methods for appropriate statistical inference.
Jerica Berge, PhD, LMFT is an Assistant Professor and behavioral health provider in the Department of Family Medicine and Community Health at the University of Minnesota Medical School. She received her PhD in marriage and family therapy from the University of Minnesota. Dr. Berge is a co-investigator on Project F-EAT and is part of the Project EAT research team. Dr. Berge’s research interest is in investigating how familial influences can create risk or protective factors for childhood and adolescent obesity. She has written papers on the influence of the significant other on health behaviors and weight status, and the association between parenting style and child health behaviors and weight status from Project EAT data. Dr. Berge is also a licensed marriage and family therapist and an approved marriage and family therapy supervisor who specializes in collaborative care and family health issues.
Jayne A. Fulkerson, PhD is an Associate Professor in the School of Nursing. She has been a project contributor and manuscript author and co-author on Projects EAT-I, EAT-II, and EAT-III. As a psychologist she conducts family-focused, community-based research. Her research is focused on changing the home food environment and promoting family meals. She blends her content knowledge in eating behaviors, family meals, childhood obesity and nutrition interventions with her skills in methodology, statistical analysis and program evaluation.
Nicole Larson, PhD, MPH, RD is a Research Associate in the Division of Epidemiology and Community Health and the Project Director for Project EAT-III. Her primary role on the study is to oversee the daily operations and data collection. She has been working on Project EAT since 2002 and used the rich data set to complete both her Master’s degree in Public Health and doctoral degree in nutrition. Working on Project EAT has allowed Nicole to explore her interests in what helps adolescents and young adults to build healthy eating patterns.
Katie Loth, MPH, RD earned her Master’s degree in the University of Minnesota’s Public Health Nutrition program and is currently in her third year of the Behavioral Epidemiology doctoral program. As the Project Director for Project F-EAT, her primary focus is to oversee the daily operations and data collection for this study as well as to work closely with members of the Project EAT team. Working on both Project EAT and Project F-EAT has allowed Ms. Loth to explore her interests in the role of family in the development of body image in adolescents and young adults, as well as how family might play a role in the prevention of disordered eating behaviors.
Division of Epidemiology
University of Minnesota
1300 S. 2nd Street
Minneapolis, MN 55454
- Powerful Girls Have Powerful Bones (Centers for Disease Control & Prevention)
- Milk Matters (National Institute of Child Health & Human Development)
- YourSELF Pages for Middle School Students (US Department of Agriculture Team Nutrition)
- Staying Active and Eating Healthy (National Women’s Health Information Center)
- HealthFinder for Teenagers (US Department of Health & Human Services)
- Do you have a smart mouth? (Center for Science in the Public Interest)
- Take Charge of Your Health: A Teenager’s Guide to Better Health (National Institutes of Health)
- Tutan Tomato: A Food Pyramid Challenge (Illinois Nutrition Education & Training Program)
- Vegetarian Nutrition for Teenagers (The Vegetarian Resource Group)
- Health Facts for Teens (The Nemours Foundation)
- Let’s Move (Childhood Obesity Task Force)
- Choose My Plate (U.S. Department of Agriculture)
- About-Face: Don’t Fall for the Media Circus
- New Moon Girls
- Kids Eat Right (Academy of Nutrition and Dietetics)
- BAM! Body and Mind (Centers for Disease Control and Prevention)
- Fuel-up to Play 60 (National Dairy Council)
- Best Bones Forever! (U.S. Department of Health and Human Services)
- Girls Health (Office of Women’s Health)
- Body Works for Guys (U.S. Department of Agriculture)
- Teens Health (Nemours Foundation)
- Take Charge of Your Health: A Guide for Teenagers (National Institute of Diabetes and Digestive and Kidney Diseases, U.S. Department of Health and Human Services)
Project EAT Resources
- University of Minnesota, School of Public Health
- Division of Epidemiology and Community Health, Public Health Nutrition
- Maternal & Child Health Bureau
- National Institutes of Health
- MCHB Library Knowledge Path: Child & Adolescent Nutrition
- Healthy People
- University of Minnesota Data Collection and Support Services
- Amherst H. Wilder Foundation Research Center
Project EAT I addressed four central research questions:
- Are adolescents eating in accordance with the Healthy People recommendations?
- Which subgroups of adolescents are at greatest risk for not meeting these objectives and need to be targeted for interventions?
- What are the direct and indirect overall contributions of socio-environmental, personal, and behavioral factors to the explained variance in dietary intake and Body Mass Index?
- What specific measures from within the socio-environmental, personal, and behavioral factors are associated with dietary intake and Body Mass Index among adolescents?
Qualitative data collected from focus groups were analyzed by the constant comparative method. Quantitative data collected from survey participants were analyzed by a variety of statistical methods according to whether the data were categorical or continuous and according to the purpose of the analysis. For details please see the individual publications from Project EAT.
To address the Project EAT I objectives data were collected in three phases:
- Focus groups with 141 adolescents
- Surveys and anthropometric measurements of 4,746 adolescents
- Telephone interviews with 902 parents
- Focus groups were conducted with 141 adolescents to insure all relevant factors effecting their eating and physical activity behaviors would be included in the model and survey.
- Surveys were administered by trained research staff to middle and high school students in the Minneapolis, St. Paul, and Osseo school districts in Minnesota. Students completed a food frequency questionnaire and the Project EAT Student Survey (n=4,746). The Project EAT Student Survey, developed by the principal investigator, Dr. Neumark-Sztainer, and research team includes questions on self-reported height and weight, potential correlates of dietary intake, and weight control behaviors. For more details about the survey please see the Surveys section below.
- After completion of the surveys, height and weight measurements were collected from students privately using a standardized protocol.
- A similar telephone questionnaire focusing on socio-environmental factors was administered to randomly selected parents (n=902) of students who completed the survey. Random selection was done after stratifying students by ethnicity in order to assure adequate representation from each group. Trained staff at the Data Collection and Support Services or Wilder Research Center administered all questionnaires.
Who participated in Project EAT?
- 50% females
- 50% males
- 34% middle school
- 66% high school students
- 14.9 (range 11-18)
- 49% Caucasian
- 19% African American
- 19% Asian American
- 6% Hispanic
- 3.5% Native American
- 4% other/mixed
More than 2,500 participants completed follow-up surveys assessing personal, behavioral, and socio-environmental constructs in the model of factors hypothesized to influence eating behaviors. Data collection was completed in June 2004.
Project EAT-II addresses questions about weight status, weight control behaviors, and dietary intake patterns targeted in Healthy People 2010:
- Have there been changes in secular trends over the past 4-5 years?
- What important changes occur as youth progress through different stages of adolescence?
- What are the most relevant socio-environmental, personal, and behavioral predictive factors during these different stages?
- How do prevalence and predictors differ for youth by gender, race/ethnicity, and socioeconomic status?
In all analyses data are weighted to adjust for differential response rates using the response propensity method for a large number of predictor variables available from the EAT-I survey (i.e., gender, native born, ethnicity/race, socioeconomic status, overweight status, parental marital status, individual’s concern about health, and most common grade in school). Survey data collected are analyzed by a variety of statistical methods according to whether the data represents categorical or continuous variables and according to the purpose of the analysis. For details please see the individual publications from Project EAT-II that will be posted online as manuscripts are published.
To address the Project EAT-II objectives and examine changes in eating patterns and weight status over 5 years, surveys were mailed to all original Project EAT-I participants for whom contact information was available in 2003-2004.
- The Project EAT-I survey was revised and two versions based on the model were developed. One version was mailed to participants who were in junior high school at time 1 (time 2 high school cohort) and a second version to participants who were in senior high school at time 1 (time 2 post-high school cohort). Some items from the original survey were dropped due to data redundancy (e.g., childhood weight) and several new items were added following focus groups with young adults that raised topics of relevance to the post-high school cohort. For more details about the surveys please see the Surveys section below.
- Between April 2003 and June 2004, Project EAT-II surveys and food frequency questionnaires were mailed to both cohorts randomly selected into 6 waves by the Data Collection and Support Services in the Division of Epidemiology and Community Health, University of Minnesota.
- An effort was made to include as many of the original participants as possible. If the first survey was not returned, participants were sent 2 reminder postcards and 3 additional survey packets. When mail was returned due to an incorrect address, staff used internet tracking services to identify a current address based on the participant’s parent’s name and last known address.
- Of approximately 3,700 EAT-I participants contacted by mail, 2,516 responded to the EAT-II survey.
Who participated in Project EAT – II?
- 55.1% females
- 44.9% males
- 32% high school
- 66% post-high school
- 17.2 years (high school cohort)
- 20.4 years (post-high school cohort)
- 6139% Caucasian
- 11.1% African American
- 17.8% Asian American
- 4.5% Hispanic
- 1.9% Native American
- 2.7% other/mixed
EAT - III
Nearly 2300 participants completed 10-year follow-up surveys assessing weight status, weight-related behaviors, and potential correlates of these outcomes. Data collection using online and mailed surveys was completed in October 2009. Details of the research design are described below and published manuscripts from Project EAT-III will be posted on the Publications page as the survey data are analyzed.
Project EAT-III aims to determine the prevalence of weight status and related behaviors, including weight control behaviors, dietary intake, and physical activity during young adulthood and trajectories of these variables during the critical transition from adolescence to young adulthood.
Project EAT-III further aims to enhance our understanding of the environmental, personal, and behavioral factors that influence weight status and related behaviors, including weight control behaviors, dietary intake, and physical activity, during adolescence and young adulthood.
The Project EAT survey was revised based on an expanded model, integrating an ecological perspective with Social Cognitive Theory. Survey development involved a comprehensive literature review, focus group discussions, and an assessment of test-retest reliability. Additional details about the Project EAT-III survey are posted online.
Survey invitation letters, providing the web address and a unique password for completing the online version of the Project EAT-III survey and a food frequency questionnaire were mailed to all original Project EAT-I participants for whom contact information was available. Participants who did not respond to the initial invitation were sent three reminder letters. The second reminder letter included paper copies of the survey and food frequency questionnaire, and all other mailings included a postage-paid card for requesting paper copies. Data collection ran from November 2008 to October 2009 and was conducted by the Health Survey Research Center in the School of Public Health at the University of Minnesota, Minneapolis.
Additional information regarding data collection may be found in the manuscript: Larson N, Neumark-Sztainer D, Harwood EM, Eisenberg ME, Wall MM, Hannan PJ. Do young adults participate in surveys that ‘go green’? Response rates to a web and mailed survey of weight-related health behaviors. Int J Child Health Hum Dev. 2011;4(2):225-237. Article
Who Participated in EAT-III?
Of approximately 3442 EAT-I participants contacted by mail, a diverse group of 1030 men and 1257 women responded to the EAT-III follow-up survey. One third of participants (31%) were aged 20 to 25 years and two thirds (69%) were aged 26-31 years.
Project EAT 2010 addresses five major research questions:
- How do weight status and related behaviors among adolescents compare with the Healthy People Objectives?
- How do different factors, including characteristics of environments (i.e., home/family, peer, school, and neighborhood environments), personal factors and behavioral factors, work together to influence weight status and related behaviors?
- What are the most important environmental, personal, and behavioral influences on weight status and related behaviors for adolescents?
- How do weight status, weight-related behaviors, and influencing factors differ across gender, ethnicity/race, and socioeconomic status?
- What secular changes in weight status and related behaviors have occurred over the past 10 years among middle school and high school students?
Surveys were administered by trained research staff to middle and high school students in the Minneapolis and St. Paul school districts in Minnesota. Students completed the Project EAT 2010 Student Survey, a food frequency questionnaire, and a physical activity questionnaire. The Project EAT 2010 Student Survey was developed by the principal investigator and research team to assess weight status, weight-related behaviors, and potential correlates of these outcomes. Trained research staff also collected student height and weight measurements using a standardized protocol.
Surveys regarding the school environment were completed by personnel at each participating school, including an administrator, food service manager, and physical activity teacher. The surveys were designed to assess school resources, policies, and practices of relevance to eating, physical activity, and weight-related harassment.
Geographic data are being used to learn about residential and school neighborhood environments. Measurements relating to local food environments, utilitarian physical activity environments, recreational physical activity environments, and neighborhood safety are being completed by the Spatial Analysis Core at the Minnesota Population Center.
Additional details about the EAT 2010 Survey are posted online.
Project F-EAT is an ancillary study to EAT 2010 (Eating and Activity in Teens) designed to examine influences within the family and home environment on eating, physical activity, and weight-related behaviors of adolescents. Project F-EAT surveys were completed by a sample of approximately 3,700 parents or guardians of the adolescents enrolled in EAT 2010. Adolescents participants in the EAT 2010 study were asked to identify up to two parents or guardians. Parents were invited to complete the survey via mail or over the telephone and a response rate of 79% was achieved. To meet the needs of this culturally diverse group of parents, both the mailed and telephone survey were available in English, Spanish, Hmong, and Somali and the telephone survey was additionally offered in Oromo, Amharic and Karen.
Project F-EAT (Families and Eating and Activity in Teens) will improve our understanding of how the family and home environment influence the eating, physical activity, and weight-related behaviors of young people.
Research questions to be addressed by Project F-EAT are:
- How do parents of adolescents describe their family and home with regard to weight culture (for example; parental weight control, parental body image, weight teasing, etc.) and the food and physical activity environments, and what are the associations with adolescents’ weight status, body image, weight control practices, dietary intake, and physical activity?
- How do parental reports of the familial and home environment, and associations with adolescent eating, physical activity, and weight-related outcomes differ across ethnicity/race, socioeconomic status, age of adolescent, gender of adolescent and parent, and weight status of adolescent and parent?
- How does the familial and home environment interact with adolescents’ individual characteristics (for example, body image, weight control behaviors, etc.), and peer, school, and neighborhood environments, to predict adolescent eating, physical activity, and weight-related outcomes?
- What have been the 10-year secular trends from 1999-2009 in parental reports of weight culture and food and physical activity environments within adolescents’ homes?
To address the Project F-EAT objectives, the parents (or other caregivers) of adolescents participating in Project EAT-III are being asked to complete a survey by mail or phone.
- The Project F-EAT survey was developed by a multi-disciplinary research team. An ecological framework developed by the research team was used to guide survey development. Each section of the survey was reviewed by a member of a review panel with an expertise in that content area. Finally, the survey was pilot tested with focus groups parents of adolescents.
- Invitations to complete the Project F-EAT survey are being mailed to the home address of parents, including up to two parents for each teenager participating in Project EAT-III. If a mailed survey is not returned, parents are also invited to complete the Project F-EAT survey over the telephone.
- Mailed surveys and telephone interviews were translated into English, Spanish, Hmong, and Somali. Parents are being mailed surveys in the language their teenager indicates is primarily spoken at home.
Additional details about the Project F-EAT Survey are posted online.
Project Results: Points of Interest
- Over the past decade (1999-2010) between Project EAT-I and EAT 2010, ethnic/racial disparities in the prevalence of obesity increased, pointing to a need for more effective interventions aimed at reaching diverse populations.
- A high number of adolescent boys (38%) and girls (50%) participating in EAT 2010 used unhealthy weight control behaviors such as skipping meals, taking diet pills, and smoking more cigarettes to lose or control their weight.
- Being teased about one’s weight in middle school or high school predicts poorer emotional well-being and use of unhealthy weight control behaviors in late adolescence and early young adulthood.
- Higher levels of body dissatisfaction during adolescence are related to greater use of unhealthy behaviors that may lead to weight gain.
- Only 30% of adolescent girls and 43% of adolescent boys were found to be getting enough calcium.
- Many adolescents skip breakfast and just 37% of participants in EAT 2010 reported eating breakfast daily.
- Participation in family meals varies widely among youth and is related to a number of positive outcomes, including better dietary intake, fewer unhealthy weight control behaviors, and better psychosocial health.
- A high number of parents/caregivers of adolescents (39%) experienced food insecurity in 2010 and were at increased risk for poor nutrition outcomes.
- Vegetarianism was reported by 6% of adolescents.
- Just over 50% of adolescent participants in EAT 2010 achieved current recommendations for physical activity by participating in at least seven hours per week.
Disparities and Trends in Weight Status
The increasing prevalence of overweight and obesity among adolescents is a major public health problem. Over the past decade (1999-2010) between Project EAT-I and EAT 2012, the overall prevalence of obesity and ethnic/racial disparities increased, particularly among boys.
Results from the most recent EAT 2010 survey indicated that approximately 19% of girls and 26% of boys had body mass index values at or above the 95th percentile, which is the cut-off point used for defining obesity in youth. Another 20% of girls and 16% of boys were overweight (defined as at or above the 85th percentile but less than the 95th percentile).
Girls: For girls, obesity was most common among African American, Hispanic and Native American youth. The prevalence of obesity was considerably lower among Asian American and White girls, but there was evidence of an increase in the prevalence of obesity over the past decade among Asian youth from 7% to 13%.
Boys: Obesity was more common among Hispanic, Asian, and Native American boys than White and African American boys. Evidence of increases in the prevalence of obesity over the past decade was observed for African American (from 14% to 21%) as well as Asian (from 21% to 33%) and Hispanic youth (from 20% to 34%).
Longitudinal results from Projects EAT-I, II, and III have also shown overweight/obesity increases among young people during the transition from adolescence to young adulthood. Among youth who were not overweight in adolescence, 34% of females and 45% of males were found to have a body mass index in the range used to define overweight or obesity when they reached young adulthood.
Dieting and Weight Concerns
The use of dieting and unhealthy weight control behaviors is common among teenagers and may counter-intuitively lead to weight gain through the long-term adoption of unhealthy behaviors such as binge eating, reduced breakfast consumption, and lower levels of physical activity. Over the past decade (1999-2010) between Project EAT-I and EAT 2010, there were decreases in the percent of young people using unhealthy weight control behaviors while healthy behaviors were found to increase.
Results from the most recent EAT 2010 survey indicated…
- Nearly one third of boys and 46% of girls went on a diet in the past year.
- Fifty-four percent of boys and 58% of girls regularly used healthy weight control behaviors such as eating less high-fat food, eating less sweets, and eating more fruits and vegetables over the past year.
- A concerning 38% of boys and 50% of the girls used unhealthy weight control behaviors such as skipping meals, taking diet pills, and smoking more cigarettes specifically to lose or control their weight.
- A smaller but quite worrisome percentage of students were the 4% of boys and 7% of girls who reported use of extreme weight control behaviors such as taking laxatives or diuretics, vomiting after meals, or fasting.
Results from Project EAT have also shown the prevalence of weight control behaviors remains high or increases among young people during the transition from adolescence to young adulthood and these behaviors tend to track within individuals over time. For example, findings from the 10-year follow-up survey of Project EAT-I participants showed…
- The prevalence of dieting increased from 22% to 28% among male participants who transitioned from middle adolescence (mean age = 16 years) to middle young adulthood (mean age = 26 years).
- The use of unhealthy weight control behaviors remained high but showed a small decrease in prevalence (from 61% to 54%) among female participants who transitioned from middle adolescence to middle young adulthood.
- Among female participants who transitioned from early adolescence (mean age = 13 years) to early young adulthood (mean age = 23 years), the prevalence of extreme weight control behaviors more than doubled from 8% to 20%.
Approximately 22% of adolescent boys and 25% of adolescent girls who participated in Project EAT-I reported being teased about their weight at least a few times per year. These young people reported teasing by both peers and family members.
These findings are concerning as being teased about one’s weight in middle school or high school was found to predict poorer emotional well-being five years later in Project EAT-II. Adolescents who were ever teased about their weight reported lower levels of self-esteem and higher levels of body dissatisfaction. Among females and older males (in high school at EAT-I), ever being teased about one’s weight also predicted more depressive symptoms five years later.
Females who reported being teased about their weight at Project EAT-I were also more likely to report frequent dieting at five-year follow-up than their peers who were not teased.
Males who reported being teased about their weight at Project EAT-I were more likely than their peers to report binge eating and the use of unhealthy weight control behaviors five years later.
Findings from Project EAT-IIII further indicate that weight teasing remains a concern as young people transition from adolescence to young adulthood. The prevalence of weight teasing remained stable among most groups and, among males transitioning from early adolescence (mean age = 13 years) to early young adulthood (mean age = 23 years), reports of experiencing weight teasing at least a few times each year were found to increase from 18% to 27%.
High prevalences of adolescents express body dissatisfaction, which was found to longitudinally predict both unhealthy behaviors and weight gain. Project EAT-I found that 46% of girls and 26% of boys had high levels of body dissatisfaction. Body dissatisfaction during the teen years is related to greater use of unhealthy behaviors that may lead to weight gain.
Findings from follow-up surveys of Project EAT-I participants at five and ten years have shown…
- Young people having higher levels of body dissatisfaction at Project EAT-I were more likely to report unhealthy weight control behaviors, binge eating, and lower levels of physical activity at five-year follow-up.
- Higher levels of body dissatisfaction at EAT-I predicted greater weight gains over time, even after taking starting body mass index into account.
- Higher levels of body dissatisfaction at Project EAT-I were further related to increased risk for depression and poor self-esteem over time.
Nutrition Recommendations vs. Actual Intake
Project EAT-I found there are large gaps between nutrition recommendations and the actual dietary patterns of adolescents.
Among the students surveyed, only 30% of girls and 42% of boys consumed the recommended amount of calcium (1300 mg or more per day). Approximately 45% of both girls and boys ate more than two servings of fruit per day, while only about 16% ate more than three servings of vegetables per day. Middle school students had higher calcium, fruit, and vegetable intakes than older students in high school.
Across ethnicity, nutrient intakes varied considerably. Fewer Asian American and Hispanic youth met calcium intake recommendations compared to their peers. However, Asian American and Hispanic youth were most likely to report eating five or more fruits and vegetables daily.
Over the five years between Project EAT-I and Project EAT-II, young people decreased their intake of fruits and vegetables as they transitioned from middle school to high school and from high school to post-high school.
Eating breakfast has been linked to better academic performance and overall dietary intake, and may also contribute to maintenance of a healthy weight.
Results from the most recent EAT 2010 survey indicated that just 37% of adolescent participants ate breakfast every day. Another 30% of adolescents ate breakfast 3-6 days a week. Of concern, 22% only ate breakfast 1-2 days a week and 11% of adolescents never ate breakfast.
Family meals are a challenge given the busy schedules of adolescents and their parents, but eating together is beneficial when it does occur. Major reasons for not having family meals include parent and adolescent schedules, adolescents’ desire for autonomy, dissatisfaction with family relationships, and dislike of foods served at family meals.
Project EAT-I found that adolescents eating regular family meals had higher fruit, vegetable, and calcium intakes than their peers not reporting regular family meals, and they drank significantly fewer soft drinks. Results from Project EAT-II further showed that young people who were having more family meals during high school had higher daily intakes of fruit, vegetables, calcium, and other important nutrients in early young adulthood.
Project EAT-III survey results showed that having more frequent shared household meals in young adulthood was associated with some markers of better nutrition. A higher frequency of shared household meals in young adulthood was predicted by having more frequent family meals during adolescence.
In addition to the observed nutritional benefits, family meals have also been cross-sectionally and/or prospectively related to higher academic performance, greater psychosocial well-being and a reduced risk of using unhealthy weight control behaviors.
Over the past decade (1999-2010) between Project EAT-I and EAT 2010, increased attention has been given to family meals in the scientific literature and popular media. Despite this attention to the benefits of eating together, results from the recent EAT 2010 survey indicated the frequency of family meals either remained constant or decreased in the homes of adolescents across different segments of the population.
Household food insecurity was experienced by almost 39% of the parents and caregivers who participated in Project F-EAT, and 13% reported very low food security. Food-insecure parents of adolescents were more likely than food-secure parents to be overweight and reported poorer nutrition-related outcomes:
- Food-insecure parents ate breakfast less frequently, consumed more sugar-sweetened beverages, and were more likely to report binge eating compared to those who were food secure.
- Among parents who reported having family dinners, those who were food insecure reported more often serving sugar-sweetened beverages at dinner and less often serving healthy items such as green salad, vegetables, and fruit compared to those who were food secure.
- In comparison to food-secure parents, those who were food insecure reported greater barriers to purchasing fruits and vegetables in terms of neighborhood access to a variety of affordably-priced and high-quality produce.
Vegetarianism was reported by about 6% of adolescents who participated in Project EAT-I, nearly 75% were females, and 75% had been so for longer than 1 year.
When asked why they were vegetarian, students reported the following top five reasons:
- To lose or not gain weight (35%)
- Do not want to kill animals (28%)
- Don’t like the taste of meat (27%)
- To have a healthier diet (25%)
- To help the environment (17%)
Vegetarians were more likely to use unhealthy weight control behaviors, particularly males. Since vegetarianism seems to have interest and appeal to adolescents, education regarding healthy vegetarianism is critical to help prevent unhealthy weight control behaviors among youth.
Activities & Sports
Physical activity has numerous benefits, including better cardiovascular health, stronger bones, and improved mental health and mood. The Physical Activity Guidelines for Americans recommend that adolescents do 60 minutes or more of physical activities every day. It is also recommended that young people limit their time spent in more sedentary activities. Specifically, the American Academy of Pediatrics recommends that adolescents spend no more than two hours on an average day with screen media, including TV and video watching as well as time spent playing video games and using a computer for activities other than homework.
Results from the recent EAT 2010 survey indicated that just over 50% of adolescent participants met the current guidelines for physical activity by participating in at least seven hours of physical activity per week.
Approximately 85% of young people exceeded the American Academy of Pediatrics recommendation for screen time and reported more than 14 hours of screen time in a given week; 47% reported more than 35 hours of screen time.
Longitudinal results from Projects EAT-I, II, and III have also shown that moderate and vigorous physical activity tends to decrease and computer use (not for work or homework) tends to increase as young people transition from adolescence to young adulthood.
The baseline Project EAT survey was completed by participants attending middle school and high school in 1998-1999.
Project EAT-II Survey for High School Students (pdf)
This 5-year follow-up survey was completed by participants who were middle adolescents in 2003-2004.
Project EAT-II Survey for Young Adults (pdf)
This 5-year follow-up survey was completed by participants who were 18-23 years in 2003-2004.
Project EAT-III Survey (pdf)
This 10-year follow-up survey was completed by young adult participants who were ages 20-31 years in 2008-2009.
Project F-EAT Survey(pdf)
This survey was completed by the parents/caregivers of young people attending middle school or high school during the 2009-2010 school year.
Project EAT 2010 (pdf)
This survey about eating, physical activity, and weight-related behaviors was completed by young people attending middle school or high school during the 2009-2010 school year.
Psychometrics for the Project EAT-III Survey (pdf)
For constructs assessed on the Project EAT-III Survey, this table provides selected psychometrics and references for the original source of measures. Additional information regarding survey development may be found in the manuscript: Larson N, Neumark-Sztainer D, Story M, van den Berg P, Hannan PJ. Identifying correlates of young adults’ weight behavior: survey development. Am J Health Behav. 2011;35:712-715.
The psychometric properties of measures found on Project EAT-I and Project EAT-II Surveys can be found in published manuscripts. There is no table of psychometrics available for these surveys at this time.